Transmission band limiting filter for CDMA transmission

While an instantaneous peak value of transmission power required to transmit data is effectively suppressed, the data can be transmitted by reducing distortions and maintaining a better frequency characteristic. In other words, while a region used to compensate for a linearity of an amplifier may be made small, a transmission system can be operated in a high efficiency and under low power consumption. A transmission system is featured by that a correcting unit is arranged at a prestage of an ROF unit in the CDMA system. In this transmission system, an instantaneous power amount is calculated, and is compared with a preset upper limit value. When this calculated instantaneous power amount exceeds this upper limit value, this power amount is detected as an instantaneous peak. Only when the calculated instantaneous power amount exceeds the upper limit value, an amplitude correction is selectively carried out so as to reduce distortions appeared in the vicinity of a region to be corrected.